Ignition cutoff device



Patented Oct. 7, 1941 UNITED STATES E ATENT GFFICE IGNITION CUTGFF DEVICE Vollie G. Cosner, Omaha, Nebr. Application November 25, 1940, Serial No. 367,110

3 Claims.

This invention relates to an ignition cut oil device and has for an object to provide a device of this character particularly adapted to cut off the ignition and. prevent an airplane from being set on fire after a crash.

Another object is to provide a warning signal associated with the device to indicate when the device is in open circuit position.

A further object is to provide a device of this character which may be reset without taking apart any of the parts of the device.

A further object is to provide a device of this character so constructed that landing jolts will not operate the device whereas a crash landing jolt will operate the device.

A further object is to provide a device of this character which will be formed of a few strong, simple and durable parts, which will be inexpensive to manufacture, and which will not easily get out of order.

With the above and other objects in view the invention consists of certain novel details of construction and combinations of parts hereinafter fully described and claimed, it being understood that various modifications may be resorted to within the scope of the appended claims without departing from the spirit or sacrificing any of the advantages of the invention.

In the accompanying drawing forming a part of this specification:

Figure l is a longitudinal section of an ignition cut off device constructed in accordance with the invention.

Figure 2 is a longitudinal sectional view taken on line 2-2 of Figure 1.

Figure 3 is a bottom plan view of the device.

Figure 4 is a fragmentary cross sectional View showing the warning signal and resetting parts of the device.

Figure 5 is a perspective view of a modified form of the invention suitable for a dual magneto ignition system, with the parts separated.

Referring now to the drawing in which like characters of reference designate similar parts in the various views, the cut off device comprises an upright substantially cylindrical casing Ill having a horizontal partition I! secured below the center of the casing. A tubular guide l2 extends upwardly from the center of the partition and opens through the bottom face of the partition. A rod I3 is slidably mounted in the guide and has its lower end extended through the partition. The rod is provided at its upper end with a dished disk It. A helical spring i5 is sleeved on the guide and on the red and is confined under compression between the partition II and the disk M. The spring normally holds a ball l6 mounted on the disk, in contact with the top H of the casing.

A spring clip I8 is secured to, and insulated from, the lower side of the partition, and a conductor wire [9 extends from the clip to the ignition mechanism. The spring clip is located at one side of the center of the partition. An angular bracket 2!] is secured to the casing and to the lower side of the partition at the opposite side of the center of the partition from the clip I 8.

An arm 2! of non-conducting material is hinged at one end to the bracket as shown at 22 and extends from the bracket in the direction of the spring clip IS. A contact bolt 23 is secured to the free end of the arm and eX- tends above and below the free end of the arm. A conductor wire 24 extends from the battery to the contact bolt. The upper end of the contact bolt is globular and is frictionally received between the jaws of the spring clip I 8 whereby to normally close the ignition circuit.

Any sudden thrust imparted to the ball IS, such as would occur in the event of a crash landing would cause the ball to move the rod l3 downwardly and the downward movement of the rod wouid move the arm 2| downwardly in a direction to carry the contact bolt 23 out of engagement with the spring clip l8 and break the ignition circuit. Landing jars or other inconsequential jars would have no effect on the ball I 5.

A helical spring 25 is connected to the arm 2! and to the casing l0 below the partition by respective eye rivets 26, and holds the arm in ignition interrupting position when the ball has once moved the arm to this position, until the arm is manually reset as will be presently described.

For manually resetting the arm 2| after each actuation, a crank 21 is disposed on the end of a hollow shaft 28, as best shown in Figure 4, the hollow shaft being rotatably mounted in a threaded bushing 29 which is engaged through one wall of the casing I O and through the instrument board 30 of the airplane and is secured thereto by the head 3| of the bushing and a nut 32 screwed on to the threaded portion of the bushmg.

The hollow shaft terminates in a disk 3-3 having a threaded annulus 34 which receives a hollow knob 35 which forms a housing for a telltale or warning lamp bulb 36. The hollow knob Oct. 7, 1941. F. w. HEYER ETAL 2,258,554

SURGICAL EMERGENCY SIGNAL- Filed Oct. 25. 1939 INVENTORS ATTO R N EYS WITN SS8 

